Pole-top switch



E. H. JACOBS.

POLE TOP SWITCH.

APPLICATION FILED APR-29,1918.

Patented Feb. 1, 1921 Now E. H. JACOBS.

POLE TOP SWITCH.

' APPLICATION FILED APR. 29, I9I8. 1,867,188. Patented Feb. 1,1921.

3 SHEETS-SHEET 2.

E. H. JACOBS.

POLE TOP SWITCH.

APPLICATION FILED APR.29, 1918. 1,367,188.

3 SHEETS-SHEET 3.

\ Patented Feb. 1,1921.

UNITED sTATEs- PATENT OFFICE. Y

POLE-T]? swi'rcrr.

ERNEST H. JACOBS, OF CHICAGO, ILLINOIS, ASSIGNOIt 'IO ELECTRICAL ENGINEERS EQUIPMENT COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION 01 ILLINOIS.

Application filed April 29, 19l8. Serial No. 231,548.

To all whom it may concern:

Be it known that I, Ennns'r H. .lAcoes, a citizen of the United States, reslding at Chicago, in the county of Cook and State of Illinois, have invented a certain new nd useful Improvement in Pole-Top Switches, of which the following is a full, clear, concise, and exact description, reference be ng had to the accompanying drawings, fornnng a part of this specification.

My invention relates to pole top switches. Switches of this class are generally employed for interrupting the current flow in a transmission line at power houses, sub-stations and at transformer towers along the line. Such switches usually are of the quick break, open air. type. They are usually mounted on a tower adjacent the sub-station, or upon a frame on top of the station. The switch is operated from a distance by an arrangement of rods and levers extending to a suitable operating handle in convenient position at the foot of the tower or other supporting structure. The present invention provides a movable switch element pivoted centrally between the two switch terminals and arranged to be rotated laterally into or out of contactjwith both terminals simultaneously.

Switches of theabove type are simple, inexpensive and-rugged, and arein demand for outdoor installations, particularly where an oil circuit breaker would be impracticable. j

My improved switch is of the above general type and is further characterized b certain novel features adding to its reliabi ity and efiiciehcy' The switch termlnals and rotatable switch member are supported on insulators which are adjustably mounted -on a supporting frame whereby they may be adjusted relative to eachother. Furtheradjustment is provided to properly aline the switch termi- 'nals and the rotatable switch members.

The clamps and insulators arepreferably universal and interchangeable, of a form described in Patent No. 1,274,555, issued to me, August '6", 1918.

Another feature of the present invention resides in the spring mounting. and the weather protection of the switch jaws. The

switch jaws are mounted for a particular rocking motion, adapting them to maximum area of contact. They are also protected against accumulations of sleet and ice by a shield or hood which closely houses the jaws, yet does not interfere with their switching operation.

Another struction of the rotatable switch arm. This arm has switch blades or contacts pivoted to its ends and has flexible eonductors extending along the arm and securely attached to the pivoted switch blades or contacts. The

main current flow passes through the flexi ble conductors'and the switch blades or contacts. The are caused by opening the switch is carried by horns mounted on the terminals and on the rotatable switch arm. These horns are pivotally mounted under spring tension, which insures the proper period of contact and separation to relieve the main switch contacts of all arcing.

Other features residing in the construetion and arrangement of parts will be apparent from the following detailed description. Some of the improvements in the present application are applicable to switches of other types, and I do not, therefore, intend to-limit these improvements to the particular form of switch herein shown and described.

In the accompanying drawings, in which I have shown one preferred embodiment of my invention,

Figure 1 is an elevational view of the pole top switch, parts being shown in section;

Fig. 2 is an enlarged elevational view of one of the switch terminals and the cooperating movable contact, parts being shown in section;

Fig. 3 is a fragmentary continuation of Fig. 2 with the exception that its plane is'at ri ht angles to Fig. 2;

ig. 4- is a plan view of one of the switch terminals showing the sleet hood and horn electrode;

Fig. 5 is a longitudinal sectional view 0 the switch terminal; 1

' Fig. 6 is a transverse sectional view'of the switch terminal Fi 7 is an enlarged section taken. on the line +-7 Fig. 8 is a plan view of one. of the'socket insulator clamps separated; v The mounting for the switch consists of two parallel pipes 1010, which usually comprise part of a frame superstructure for supporting a number ofelectrical fittings.

feature is embodied in the con-' of Fig. 1; and

The insulators 11, .12 and 13 for mounting the switch terminals 14, 15 and rotatable switch arm 16 respectively, upon base plates 17 seated astride the pipes are supported 10. These plates have extending claws 18 whichpartly embrace thepipes and serve to lguide'the plates 17 along the pipes.

petticoat type, particularly adapted for outdoor service, and

beads of substantially have circumferential the same diameter formed in their upper and lower ends. Universal insulator clamps 24 engage the lower beads and are bolted to the plates 17 and 26 by four feet 25 integral with each clamp. I

Theseclamps comprise two semi-circular clamping bands which are bolted together by bolts 27 passing through lugs 28 extending out from the ends of the bands.

I journaled in a socket type if desired.

The middle insulator 13 is reinforced by a pin 29, shown in dotted lines, which is cemented in a socket in the center of the insulator and which has radial arms rigidly attached to the plate 26. This pin prevents turning of the insulator 13 in the clamp 24 during rotation of the switch arm 16, and moreover braces the insulator against tilt- 1ng in the clamp. This pin and the insulator clamp 24 are described 'in my copending application. The other insulators 11 and 12 may be provided with pins of this The plate 26 supporting the middle insulator, is bolted to another plate 31 which has an annular recess. fitting over a hub 32 projectin up from the surface of the base plate 1 and has a bearing stud 33 boss formed in the plate 17. A nut 34 threads over the end of the bearing stud 33.

Clamped to the upper bead of the insulator 13 is another insulator clamp 35. This clamp is 'divided into two. semi-circular bands which are clamped together by bolts 36 passing through lugs extending from the ends of the bands.

The switch arm 16 is supported across the top of the insulator 13 by means of a ribbed plate 38, which is secured by bolts 39 to a plate on the top of the insulator clamp 35. As shown in Fig. 7, the switch arm 16 consists of an inverted channel 41, the limbs of which seat on the outside of longitudinal ribs 38', formed on the plate 38. The channel 41 and the 'plate 38 are rigidly clamped together by bolts 42, pass- The crabs have by a strap 49 ing up through the webs of the plate and channel.

Extending from the ends of the channel 41 are the links 44 which bear the switch blades 45. These links are pivoted inthe channel 41 upon bolts 46 and the two links are electrically connected by the flexible copper ribbons 47 extending through the channel 41. These copper ribbons are perforated for the passage of the bolt 46 and are disposed above and below each link 44. The link 44 and ribbons 47 are maintained in firm contact by spring washers 48 above and below the ribbons.

The pivotal movement of the links 44 is confined between the limbs of the channel 41, and'each link is \guided horizontally riveted or welded to the channel 41 and extending across the open bottom of the same. The said link 44 is narrower .than the width of the channel in the bar 41 and being yieldingly clamped thereto at one end by the bolt 46 and spring washers 48 can swing from side to side in said channel, that is, it is not rigid with the channed 41 and can yield slightly. In closing the switch the pivotal connections of the links 44 with the switch arm 16 permits the swinging of the arm to its closed position even though the blades 45 might be entered between their respective jaws 68 and 69 before the arm reaches its limit, and in opening the switch the said limited pivotal movement permits the easy starting oflthe arm16 before the blades begin to move,thereby permitting a hammer action to free the device of ice, if such action is necessary. The flexible connections pressed upon the links 44 by the spring washers 46 tend to hinder pivotal movement and also serve to provide a firm and sufficient contact at the pivotal connection.

vThe copper straps or ribbons 47 are less expensive and more readily attached than flexible cables. I do not intend to exclude the use of flexible cables but find the ribbons more advantageous.

The switch terminals 14 and 15 are mounted in clamps 52 on the upper beads of the insulators l1 and 12. As shown in Figs. 2 and 8, each clamp comprises the two semi-circular clamping bands 53 and 54, the former band having a split socket ring 55 formed integral therewith. These bands are preferably slotted about their circumference as shown, to afford a slight resiliency whereby they may more readily conform to the annular bead 56 on the insulator. They are clamped upon this head by bolts 57 extending through apertured ears 58 projecting from the ends of the bands. These clamps may be made of malleable iron, brass or bronze. I find that brass or bronze is more yielding and has less tendency to break the beads on the insulators.

Eachswitch terminahconsisting of the switch jaws, sleet hood andarcing horn, is supported upon a base plate 59. An annular plug 61 is attached to the under side ofthis plate by cap screws 62 and is arranged to thread down into the split socket ring 55 as indicated at 63. The socket ring 55 issplit and has lugs 65 extending laterally from the ring on each side of the slot. A lug" 66, projecting up from the band 54, is arranged to engage between the lugs 65 and to be clamped there by the bolt 67 which passes through alining holes in the three lugs.

When it is desired to adjust the switch terminal vertically, in order to bring the switch jaws into proper register with the switch blade 45, the entire terminal is rotatedto screw the plug 61' up or downin the socket ring 55. The terminal is rigidly held in any adjusted position by tightening the bolt 67, which clamps the socket ring about the plug 61. The lug 66 is sufliciently narrow so as not to interfere with this action, the function of the lug being to connect the 7 split side of the socket ring with the band 54.

Considering now the construction of the switch terminals and referring to Figs. 4, 5

and 6, a pair of switch jaws 68 and 69, are

flexibly mounted between the base plate 59 and a hood 71, which extends out over the switch jaws and protects the same against collection of sleet and ice. integral bosses? 2 and 7 3 extending up and supporting the hood71, Bolts 74 pass down throu h the bosses 75 and 76 cast on the hood 71 and tap into the bosses 72 and 73.

The lower switch jaw 69 has an integral stud 77 which extends loosely into a socket 78 on the surface of the base 59. It will be noted that the base of thestud 77 has a beaded enlargement 77' which bears on the rim of the socket 78 and affords a spherical seating surface which will permit a slight rocking motion of the switch jaw 69 in any direction to adjust itself to the under surface of the switch blade 45. V

A guiding lug 81 projects down from the jaw 69 and is adapted to abut against the raised socket 78. This lug receives the thrust produced when the switch blade 45 strikes the switch jaws. The upper jaw 68 has a similar lug 82 which is adapted to 'abut against a raised socket 83 formed on the under side of the sleet hood 71. A compression spring 85 is confined in this socket and encircles a stud 86, on the upper switch jaw 68.

To the rear ends of these switch jaws are riveted laminated copper ribbons 87. These ribbons engage above and below the con nector block 88 which has the apertured boss portion 88' adapted for receiving the The base 59 has.

line wire 89. A tongue, 95, projectiri'gerrom' of the switch blade 45;

The connector block 88 and lower ribbon 87 seat in a channel shaped lug 91 which projects up integrally from the base 59 and has two marginal flanges embracing the sides of the ribbon and block, as best shown in Fig. 6. similarly formed channel member 92 embraces the upper ribbon 87 and connector block 88. A bolt 93 passes down through the block 92, the ribbons and connector block and taps into the base 59.

The switch blade 45 in entering the switch jaws will raise the upper jaw 68 against the spring 85 and the two jaws, being flexibly mounted, will rock or til in any direction to accommodate-the switch blade. Thus the action of the switch will always be free from jamming or from insecure or edge contact, even where irregularities exist in the mounting, due to slight inaccuracies in. the insulatorsand the clamps. The front ends of the switchjaws are formed with flaring lips, which arereinforced by ribs 98, these lips serving to properly guide-the switch blade between the switch jaws. inclined front'end 71 of the hood 71 projects out over the ends of the switch jaws to protect the same, and the downwardly extending portions 71 and 71 along the side and rear of the hood, act as water sheds for partially inclosing the switch jaws.

The housing formed by the base member 59 and the cover or hood 71 forms a U-shape The upwardly member within which are mounted pivotally cured'by the bolts 46 at each end of the switch arm 16 and supports a horn 102. A coiiperating horn 103 is pivotally mounted on each of the switch terminals, as shown in the previously described figures. The bracket 104, supporting this horn, is formed integral with a sleeve hub 105, journaled between the base plate 59 and the sleet hood 71. The lower end of the sleeve 105 is open and is journaled in a ring socket 106 formed integral with the base plate 59. A bolt 107 extends down through the sleet hood 71,

and sleeve 105, and threads into the base 59. The spring 108 is coiled about the shank of this bolt and has its ends attached to'the base 59 and to the sleeve 105. The spring tends to revolve the sleeve 105 and bracket 104 counter clockwise as viewed in Fig. 4. The horn is normally held in the position shown, by the engagement of a projection 109 on the surface of the hub 105, with a I lug 111 on the ring socket 106.

The horns are composed of rods of halfround section, bent back to form a diverging horn gap. It will be noted that the horns 103, on the switch terminals, are

bent both upwardly and laterally to provide the cam surfaces 112 and that the horns 102 are set at an angle to the switch arm so that with the switch closed both horns will occupy the relative positions illustrated in Fig. 4.

The switch is operated by the rotation of the arm 114, extending from the plate 31 (Fig. 1). -A number of such'switches may be operated simultaneously as in controlling a three phase circuit. The block 115 is swiveled to the end of this rod and has attachment with a rod 116 arranged to be reciprocated through a crank and shaft or any suitable mechanical means extending down from "the pole or superstructure to a point accessible for operation.

In opening the switch from its closed position, as shown in Fig. 4, the switch blade carrying the horn 102, is swung to the left,.the horn 102 strikes the cam surface 112 of thehorn 103, and swings the horn 103, out of its path, the horn 103, being held in contact with the horn 102 by the spring 108. Thehorns remain in contact until after the blade leaves the switch jaws and being the last part of the switch to separate, they carry the arc, and the final break of the arc occurs between the divergent upper ends of the horns. Upon closing the switch, the parts to make the with the cam surface 112,

at which time the blade 45 contact first are the horns 102 and 103, the curved outer end of the horn 102 engages of the horn 103, and pushes the horn 103 out of its path against the spring 108 and as the switch continues to close, the horn 102 slides along in contact with the horn 103, which is held in contact with the horn 102 by the spring 108, until the further rotation of the horn 103 is stopped by the stop pins 109 and 111,

has entered between the switch jaws 68 and 69, thus providing an ample path for the current. The further closing of the switch carries the blade 45 to its final position between jaws 68 and 69, and separates the horns 102 and 103,'as shown in Fig. 4. Thus the horn electrodes always make contact first on closing the switch and break contact last, relieving the switch bladesand jaws of arcing. The horns are preferably of a hard grade of iron and can. be cheaply and easily renewed.

I do not intend to ticular 'details herein I claim! 1. In combination, a switch arm comprisbe limited to the parshown and described.

ing a channel member pivoted at its center for rotative movement, switch blades pivotally supported at the endsof said channel member, and a flexible conductor disposed in said channel member and having connection with said switch blades.

2. In combination, a switch arm comprising a main supporting member pivoted at its center for rotative movement, switch blades pivoted at the ends of said member, and a flexible conductor strung along said member and having connection with said pivoted switch blades.

3. In combination, a pivoted switch arm, a switch blade pivotally supported at the end of said switch arm, and a flexible conductor extending along said switch arm and having connection with said switch blade.

4. In combination, a switch arm comprising a main supporting member pivoted at its center for rotative movement, switch blades on the ends of said member, a flexible conductor extending along said member and connecting said switch blades, said switch blades having pivotal movement at the ends of said member, said flexible conductor tending to hinder said switch blades in their pivotal movement.

In combination,an insulator, a clamp on said insulator, arotatable switch arm supported on said clamp, said switch arm comprising a channel member, pivoted switch blades extending from the ends of said channel member, and a plurality of flexible conducting ribbons disposed in said channel member and c nneeting said switch blades.

6. In combination, an insulator, a clamp on said insulator, a terminal supported on said clamp, and means for adjusting said terminal vertically on said insulator.

T. In combination,an insulator, a clamp on said insulator, a socket in said clamp, and a terminal having socket, whereby said terminal may be adjusted relative to said insulator.

'3. In combination, an insulator, a clamp on said insulator, a threaded socket in said clamp, a terminal, a threaded plug on said terminal engaging in said socket, and means for holding said plug in any adjusted position in said socket.

9. In combination, an insulator, a clamp on said insulator, a socket in said clamp, a terminal, a plug on said terminal, said plug threading into said socket and means for contracting said socket about said plug to hold said terminal in any adjusted position.

10. In combination, a supporting member, a terminal mounted on said supporting member and plug and socket means for adjusting said terminal relative to said supporting member.

11. In a switch terminal, a housing comprising abase and a hood mounted thereon,

switch jaws mounted betweensaid base and said hood, and a horn gap electrode pivoted 13. In combinatlon, a terminal base, a pair of switch jaws mounted on said base, a protecting hood over said jaws, ,a bracket piv-- oted on said base and hood, an arcing horn supported in. saidbracket, and spring means tending to hold said horn in a predetermined position.

1 1. In combination, a supporting member,- insulators mounted foradjustable movement o switch aws, a switch frame, sockets onthe along said supporting member, switch terminals carried by said insulators, and means for adjusting said terminals perpendicularly of said supporting member.

15. In a switch, a supporting member, a plurality of lnsulator units -on said supporting member,each of-said insulator units com prising a base member shiftable along said supporting member, aninsulator mounted on said base member, a clamp on said insulator,

aswitch terminal attached to said clamp, and meansfor adjusting said switch terminal relative to said clamp.

16. In combination, a supporting frame,

insulators shiftable along said frame, switch.

terminals mounted on said insulators, a switch arm centrally pivoted on one of said insulators, switch blades pivotedto the ends of said switch arm, switch jaws mounted on said switch terminals for receiving said blades, said switch jaws being self adjusting to contact with said blade, horn gap electrodes on the ends of said switch arms, and cooperating electrodes pivotally mounted on said switch terminals.

17. In combination, a stationary contact, a movable contact movable horizontally to and from engagement with the stationary contact, a horn electrode pivotally mounted on the stationary contact and extending vertically and a cooperating horn on the movable electrode extending vertically.

18. In combination, a stationary contact,

a movable contact movable horizontally to and from engagement with the stationary contact, a horn electrode pivotally mounted on the stationary contact and extending vertically, a horn on the movable electrode extending vertically, and a protected spring yieldingly holding the pivoted horn in the path of the horn on the movable contact.

19. In a switch device of the. kind deaws,

scribed, a horizontal switch arm comprisinga channel bar having its open side down and pivoted at its center for rotative movement,

switch :blades' pivotally sup rted at the ends of the bar', and a flexible conductor disposed in said channel bar and having connections with said switch blades.

20. In a switchterminal, a base, a weather hood carried by the base, a pair of switch jaws-carried by the base beneath said hood, a hollow hub member pivotally moulit-ed between the base and hood, a horn .gap electrode carried by said hub member and proj ecting above said hood and a spring within said hub for yieldingly holding the hub memher in one direction.

21. In an electric switch, a pair of opposed switch jaws, a switch frame, sockets and cooperating projections on the jaws and frame, a connector block and flexible connectors connecting said jaws with said connector block. 7 j Q 22. In a switch terminal, a pair of opposed engaging in said sockets, a spring between the housing and one of the jaws, pressing said jawstogether, and flexible connectors connecting said jaws to the housing.

24.-In a switchterminaL-a pair of oppos'ed switch jaws, a switch frame, sockets on said frame and projections on backs of the jaws for entering saidsockets, a connector block, flexible connectors connecting the jaws to said block, the outer ends of'the jaws being divergent to direct a blade between them, the said sockets and projections formed to permit the jaws to rock'to accommodate themselves to'the opposed sur j faces of an interposed blade.

25. In a switch terminal, a pair of op-- posed switch jaws, a switch frame, cooperating sockets and projections on the frame and jaws, spring means'between the blades and frame for pressing said jaws toward each other, a connector block, flexible connectors connecting the. jaws to said block, the outer ends of the jaws being divergent to direct a switch blade'between' them, the

sockets and projections formed to permit the jaws to rockto conform with, the contacting surfaces of an interposed blade.

26.'-In a switch terminal, opposed switch a switch frame, sockets on the frame and cooperating projections on the backs of the jaws for engaging in the sockets, oneof the jaws movable from and toward theiother jaw, a spring interposed between, the moving the movable sockets on the housing in which able jaw and the frame for yieldingly holdjaw toward the other j aw, a conductor block carried by the frame, flexible means connecting said jaws with said block, the outer ends of the jaws provided with inclined surfaces for engagement with a switch blade for separating said jaws as a blade is inserted between them, the cooperat ing sockets and projections formed to permit the jaws to rock to follow the blade.

27. In a switch, two opposed switch .jaws, a switch housing, means floatingly mounting the jaws on the housing, means yieldingly holding the jaws pressed toward each other and permitting them to separate when a switch blade is forced between them, and projections on the jaws for engagement with the housing to take the thrust of'an entering blade.

28. In a switch, a housing, two opposed switch jaws, cooperating loosely fitting projections and sockets for loosely mounting the jaws on the housing, the jaws having divergent ends providing a wedge shaped mouth to receive a switch blade for entrance between the jaws, and projections on the jaws for engagement with the housing to transmit the impact of an entering blade.

29. In a switch, a housing, two opposed switch jaws, projections on the jaws, and

the projections are loosely engaged, spring means pressing said jaws toward each other, said jaws having divergent ends for wedgingly receiving a'switch blade, and projections on the jaws adapted to engage said sockets to withstand the impact of an entering blade.

30. In a switch, a housing, two opposed switch jaws, cooperating projections and sockets on the jaws and housing loosely mountlng the jaws on the housing, means yieldingly holding the jaws pressed together, flexible means connecting the jaws with the housing, v.said jaws having divergent ends for wedgingly receiving a switch blade, proectlons on the jaws for engaging the housing to withstand the'impact of an entering switch jaws,

blade, and a stop on the housing, independent of the jaws, for limiting the entering movement of the blade.

-31. In-a switch, a housing, two opposed cooperating projections and sockets on the .'aws and housing loosely housing, the forward ends of the jaws formed to wedgingly receive a switch blade for forcing said jaws aws toward each other,

apart, a spring for yieldingly holding said a connector block secured to the housmg, flexible connectors spanningsald block and secured to said aws, sa1d block positioned in the path of an entering blade and adapting to limit the inward movement thereof, said jaws free to conform to and with an interposed blade.

32. In combmation,' a U-shaped frame member, a pair of switch jaws pivotally mounted at their centers on and between the legs of the U, and a stop member mounted on said frame member at the bottom of the U.

33. In combination, a U-shaped frame member, a pair of switch jaws mounted for universal rocking motion at their centers on and between the legs of the U and spring means tending to-press said jaws together.

34. In combination, a U-shaped frame member, a pair of switch jaws pivotally mounted at their centers on and between the legs of the U, spring means for pressing said jaws together and flexible connecting means for connecting the inner ends of said jaws to a common terminal member.

35. In combination, a U-shaped frame member, a pair of switch jaws pivotally mounted at their centers for universal rocking motion on and between the legs of the U, a stop member at the rear end of said jaws, and flexible leads connectin the rear ends of the jaws to said stop member.

36. In combination, a pair of rigid floating switch jaws, a blade adapted to be thrust between the jaws, means for imposing pressure substantially centrally on sald jaws to hold them yieldin ly pressed toward each other and to grip t 1e blade between them, a common terminal and flexible leads from the jaws to said common terminal {Hid jaws havin shoulders for preventing longitudinal dlsplacement of the jaws by the entering blade.

37. In combination, a pair of rigid switch jaws having each a central projecting hearing member, supporting means lying on the outside of said jaws and having a socket for each of said bearing members and permitting of limited universal movement of the jaws, spring means tending to press said jaws together, a terminal mounted on said supporting means, and flexible means between said terminal and each of the switch aws.

J 38. In combination, a pair of switch jaws, relatively stationary means upon which said jaws are loosely mounted substantially centrally for universal rocking motion, means holding said jaws yieldingly pressed toward each other, and a pivoted switch blade adapted to be forced between and gripped by said jaws.

39. In combination, a pair of switch jaws, a relatively stationary frame comprising a weather hood extending over said jaws and providing bearing means on the outside of each of said jaws, said jaws being pivoted substantially centrally for universal motion, means yieldingly holding said jaws toward each other, a terminal mounted on said frame member and flexible conductors connected to the inner ends of said jaws and said terminal.

40. In a switch, a pair of switch jaws, an external frame member embracing both of the jaws, saidjaws having a central bearing on said frame member about which they are mounted to rock, means yieldingly pressing rear or outer surfaces, said projections lying substantially centrally of the jaws, supporting means embracing said jaws and having sockets engaging the"projecting bearings, and means for yieldingly holding said jaws in engagement with a switch blade.

42. In combination, a pair of switch jaws having engaging surfaces facing toward each other for engaging a switch blade, said jaws having bearing projections on their rear or outer surfaces, said projections lying substantially centrally of the jaws, supporting means embracing said jaws and having sockets engaging the projecting bearings, means for yieldingly holding said jaws in engagement with a switch blade, a terminal member and flexible leads connecting the terminal member with said switch jaws.

43. In combination, a pair-of switch jaws, supporting'means lying outside of and embracing both the jaws for holding the same, said jaws having universal movement on said supporting means, spring means bettween said supporting means and one of the jaws for pressing the jaws toward each other, astop block back of said jaws and flexible conductors connecting the jaws to the stop block. I

44. In an electric switch, a pair of opposed switch jaws, a frame, one of said jaws and said frame having a cooperating socket and a projection, spring means for said jaw, a connector block mounted on said frame and a flexible conductor connecting said one jaw and said block.

45. In combination, a pair of mounting bars spaced apart, a base member having claws for engaging said bars, an insulator having a pivot extending into said base and lying between said bars, a switch arm carried by said insulator, said switch arm being adapted to swing about said pivot and a clamp lying on each side of the pivot and having claws engaging the side of the bars opposlte the claws of the base member.

46. In combination, a hollow switch arm comprising a rigid self supporting member mounted for pivotal movement, a contact blade mounted at one end of the switch arm and a conductor which is not self supporting connected to the blade and being carried within and by the rigid member.

47. In an electric switch, a pair of rigid switch jaws lying opposite each other, a frame for supporting said switch aws, one of said jaws and said frame having cooperating means for permitting a lateral motion and a limited rocking motion of said one switch jaw, spring means for holding said jaws in contact with an interposed switch blade, a connector block mounted on said frame and a flexible conductor connecting said one jaw and said block.

48. In combination, a pair of pipe supporting members spaced apart from each other but lying substantially in parallel relation, a base member having claws for engaging said bars, a pin member pivoted in said base member centrally between the bars,

clamping means lying on theopposite side of said pipe members, said clamping means having claws engaging said bars for securing the base member to said bars, an insulator mounted on said pin and movable therewith and a conductor rigidly secured to the top of the insulator and movable therewith about said pivot pin. i

49. In combination, apair of pipe members, terminal insulators clamped to said pipe members a suitable distance apart, a

pivotal insulator clamped to said pipe members between said terminal insulators, said pivotal insulator comprising a base clamped to the pipe members and a pivot pin mounted in the base member and secured to the insulator, a switch blade mounted on the pivotal insulator, stationary contacts mounted on the terminal insulators, said contacts adapted to cooperate with the switch member and meanspermitting of independent vertical adjustment of the contact members on the terminal insulators.

In witness whereof, I hereunto subscribe my name this 26th day of April, A. D. 1918.

i ERNEST H. JACQBS.

It is hereby certified that in Letters Patent No. 1,367,188, granted February 1, 1921, upon the application of Ernest H. Jacobs, of Chicago, Illinois, for an improvement in Pole-Top Switches, an error appears in the printed specification requiring correction as follows: Page 5, line 116, claim 25, for the word blades read jaws; and that'the said Letters Patent should be read with this correction therein that the same may conforrn to the record of the case in the Patent Ofiice.

Signed and sealed this 8th day of March. A. D., 1921. i

M. H. COULSTON,

[SEAL] Commissioner of Patents. 01. zoo-48. 

